The present invention relates to the field of watthour meter testing devices and more specifically, but not by way of limitation, to a watthour meter test device and method having an optical pickup for testing electromechanical and electronic watthour meters.
Metering devices are located at residential and commercial customer locations as a means for electricity providers to measure electrical consumption. Watthour meters are commonly employed to measure electrical consumption at these locations. Watthour meters are typically electronic or electromechanical.
The electromechanical watthour meter is essentially an electric motor that runs in proportion to the power being used by the customer. Electromechanical meters employ a disc that is centrally disposed in the meter such that at least a portion of the disc is visible from the face of the meter. The disc is rotated by the meter""s electric motor relative to power consumption. For measurement purposes, these discs include holes extending through the discs or marks or indicia on an upper or outer peripheral edge of the disc. The electrical consumption is relative to the disc""s rotation between the hole or marks over a give time-interval.
Electronic watthour meters are generally solid-state and measure electrical consumption electronically. Electronic meters are provided with an indicator light visible on the face of the meter that flashes periodically relative to electrical consumption.
Watthour meter manufacturers, as well as electric utilities, employ testing equipment to verify the accuracy of the watthour meters. For testing, a known amount of power is applied to the watthour meter and compared to that measured by the rotation of the disc.
The testing devices necessarily include a means for detecting the rotations of the disc on electromechanical watthour meters or the flashing light on electronic meters. One such detector is the C-sensor, which includes a light transmitter and receiver used to detect the hole in the discs of electromechanical watthour meters. Thus, as the disc rotates, transmitted light projects through the hole in the disc and is detected by the receiver of the C-type sensor. The power consumption measured by the disc rotation of the watthour meter and detected by the C-sensor is compared to the known power applied to the watthour meter by the watthour meter testing device. In this manner, the accuracy of the watthour meter can be determined.
C-sensors are unable to detect black marks on the upper or outer edge of the discs of electromechanical watthour meters. Instead, various methods for detecting these marks have been attempted. However, non-standardized meters are marked differently. Testing electronic watthour meters is equally challenging, since these meters are also not standardized. Also, different detection systems are necessary for different watthour meters. Present test device systems are unable to accurately discern the markings on electromechanical watthour meters, while consistently measuring electronic meters.
For this reason, a new and improved watthour meter test device and optical pickup is needed.
As mentioned above, C-sensors are unable to detect black marks on the upper or outer edge of the discs of electromechanical watthour meters. The inventor of the present was the first to identify the problems raised by modern electric and electromechanical watthour meters that that exposes the shortcomings of present test devices. When employing transmitters to transmit a light onto the disc surface or edge such that the light is reflected from the disc, a receiver is positioned to detect the reflected light and determine the location of the black mark on the disc based upon the attributes of the reflected light signal.
However, difficulties arise when the disc is provided with numerous black marks, only one of which, such as the thickest or longest, is intended for power consumption measurement. The lack of standardization in the watthour meter industry adds to the problem, since it is the prerogative of every manufacturer to mark the discs differently. Discerning ambient light from the reflected light further magnifies the difficulty in detecting the marks on the discs. For this reason, current detection devices are incapable of accurately detecting or discerning the relevant black mark from the other marks on the disc surface or edge because of the varied sizes, placements and other factors.
Measuring electronic watthour meters requires detecting the light flashes on the face of the meter. The difficulty with testing electronic watthour meters is detecting indicator lights having non-standardized attributes, such as those having a wide color range. Discerning ambient light is similarly problematic when detecting the indicator lights on electronic watthour meters.
Considerably different detection systems are necessary to detect the holes through the discs, black marks on the discs of electromechanical watthour meters, as are system for detecting the light flashes from electronic watthour meters. Current systems are unable to accurately discern the relevant black mark on the discs of electromechanical watthour meters while consistently detecting the wide color range of lights provided on numerous electronic meters. The present invention provides a novel solution to these problems.
In one aspect, the present invention is directed to a watthour meter test device for testing electromechanical and electronic watthour meters. The watthour meter testing device has a housing provided with a socket adapted to receive a watthour meter. The watthour meter testing device is provided with current and voltage generators. The current generator communicates with the socket and is adapted to communicate a current to the watthour meter. The voltage generator communicates with the socket and is adapted to communicate a voltage to the watthour meter.
The watthour meter testing device further including an optical pickup and a measurement device. The measurement device is in communication with and adapted to determine the current and voltage communicated to the watthour meter. The optical pickup is in communication with the measurement device and is adapted to detect a consumption indicator on the watthour meter. The optical pickup includes a transmitter positioned to transmit a light signal to the watthour meter and a receiver positioned to detect light adjacent the watthour meter.
The watthour meter testing device also includes a switch in communication with the transmitter and the receiver. The switch has a first position to activate the transmitter to transmit the light signal to the consumption indicator of the watthour meter and activate the receiver to detect the light signal reflected from the consumption indicator of electromechanical watthour meters. The switch further having a second position to activate the receiver to detect a consumption signal from the consumption indicator of electronic watthour meters.
In one embodiment, the watthour meter test device of also includes a current communication line connected at a first end to the current generator and at a second end to the socket. The watthour meter testing device also includes a voltage communication line connected at a first end to the voltage generator and at a second end to the socket. The measuring device further communicates with the current communication line and the voltage communication line.
The optical pickup may further include a housing connected to the housing of the watthour meter test device, the housing of the optical pickup having an outer surface defining an inner retaining space. As such, at least a portion of the transmitter and at least a portion of the receiver are disposed within the inner retaining space of the housing of the optical pickup. The housing of the optical pickup also includes a first end provided with a lens to concentrate the light signal generatable by the transmitter to the consumption indicator of the watthour meter and to concentrate the light adjacent the watthour meter onto the receiver.
In one aspect of the present invention the watthour meter testing device may be provided with a phantom load communicated to the watthour meter instead of current and voltage generators in communication with the socket and connectable watthour meter. The watthour meter testing device provided with a measurement device in communication with and adapted to determine the load communicated to the watthour meter.
In yet another aspect, the present invention provides an optical pickup device for detecting a consumption indicator on a watthour meter. The optical pickup includes a light source, a modulator and a light detector. The light source is adapted to generate a light signal and the modulator operably coupled to the light source such that the light source produces the light signal having a frequency.
The light detector is disposed so as to receive a consumption light from the consumption indicator on the watthour meter. The light detector is operative to generate a consumption signal indicative of receiving the consumption light from consumption indicator. The optical pickup further includes an ambient light filter, an amplifier and an indicator.
The ambient light filter is operably coupled to the light detector. The ambient light filter is adapted to eliminate an ambient light portion of the consumption signal generated by the light detector. The amplifier is adapted to receive the consumption signal from the ambient light filter. The amplifier adapted to amplify the consumption signal having the light portion eliminated by the ambient light filter. The indicator operably coupled to receive the amplified consumption signal and generate an indication relative to the electrical consumption measured by the watthour meter.
In one embodiment, the optical pickup may further include a transmission line and a reception line. The transmission line has a first end and a second end. The first end of the transmission line is disposed adjacent the light source and adapted to communicate the light signal from the first end to the second end of the transmission line and to the consumption indicator on the watthour meter. The reception line has a first end and a second end. The first end of the reception line is disposed adjacent the consumption indicator on the watthour meter to receive the consumption light and communicate the consumption light to the second end of the reception line disposed adjacent the light detector.
In yet another embodiment, the light detector is further defined as a wide spectrum light detector, while in other embodiments, the light detector is further defined as a wide spectrum light phototransistor. In other embodiments, the optical pickup may also include a modulation detector operably coupled to receive a consumption signal from the ambient light filter. The modulation detector detecting a portion of the consumption signal having the frequency of the light signal generated by the light source and modulated by the modulator. As such, the modulation detector eliminates a portion of the consumption signal other than the portion of the consumption signal having the frequency of the light signal generated by the light source and modulated by the modulator.
In other embodiments, the modulator modulates the light signal in a range of from about 13.5 to 14.0 kHz and wherein the modulation detector detects the portion of the consumption signal modulated in a range of from about 13.5 to 14.0 kHz.
In another aspect, the present invention provides a method of detecting a consumption indicator on electromechanical and electronic watthour meters. The method includes providing an optical pickup having a switch provided with a first position and a second position. The method provides for switching to the second position of the switch to detect the consumption indicator on electronic meters and detecting a consumption light adjacent the consumption indicator of the watthour meter.
The method includes generating a consumption signal relative to the consumption light, the consumption signal having an ambient light portion. The method provides for filtering the ambient light portion of the consumption signal and amplifying the consumption signal. The method further includes generating an indication perceivable to a user relative to the electrical consumption measured by the watthour meter.
The method also includes switching to the first position of the switch to detect the consumption indicator on electromechanical meters and generating a light signal having a frequency. The method provides for transmitting the light signal onto the consumption indicator. The method include, in other embodiments, modulating the light signal at a frequency and may include detecting a portion of the consumption signal modulated at the frequency of the light signal. In yet other embodiments, the method includes detecting the modulated portion of the light signal is in response to switching the switch to the first position.
In yet another aspect, the present invention provides a watthour meter testing device for testing electromechanical and electronic watthour meters having a consumption indicator on the watthour meter. The watthour meter testing device includes a measuring device, a switch, a transmitter and a receiver. The measuring device communicates with the power measured by the watthour meter.
The switch is operable to test electromechanical watthour meters in a first position and operable to test electronic watthour meters in a second position. The transmitter communicates with the switch. The transmitter is operative to transmit a light signal to the consumption indicator when the switch is in the first position for testing electromechanical watthour meter. The receiver is operative to detect light adjacent the watthour meter.
The receiver provided with a filter operative to filter ambient light and operative to detect the light signal transmitted from the transmitters reflected from the consumption indicator on the watthour meter when the switch is in a first position. The receiver is further operative to detect a consumption light signal emanating from the electronic watthour meters when the switch is in a second position.
In yet another aspect, the present invention provides an optical pickup for detecting a consumption indicator on electromechanical and electronic watthour meters. The optical pickup includes a switch, a transmitter and a receiver. The switch is operable to test electromechanical watthour meters in a first position and operable to test electronic watthour meters in a second position.
The transmitter is adapted to transmit a light signal to the consumption indicator when the switch is in the first position for testing electromechanical watthour meter. The receiver is adapted to detect light adjacent the watthour meter. The receiver provided with a filter to filter ambient light and to detect the light signal transmitted from the transmitter and reflected from the consumption indicator when the switch is in the first position. The receiver is further operative to detect a consumption light signal emanating from the electronic watthour meters when the switch is in a second position.
In yet another aspect, the present invention provides a watthour meter testing device for testing electromechanical and electronic watthour meters having a consumption indicator on the watthour meter. The watthour meter testing device includes a measuring device, a switch, a transmitter and a receiver. The measuring device communicates with the power measured by the watthour meter. The switch is operable to test electromechanical watthour meters in a first position and operable to test electronic watthour meters in a second position.
The transmitter transmits a light signal to the consumption indicator when the switch is in the first position for testing electromechanical watthour meter. The receiver detects light adjacent the watthour meter. The receiver provided with a filter operative to filter ambient light and operative to detect the light signal transmitted from the transmitter reflected from the consumption indicator on the watthour meter when the switch is in a first position and further operative to detect a consumption light signal emanating from the electronic watthour meters when the switch is in a second position.
In yet another aspect, the present invention provides an optical pickup for detecting a consumption indicator on electromechanical and electronic watthour meters. The optical pickup includes a switch operable to test electromechanical watthour meters in a first position and operable to test electronic watthour meters in a second position. The optical pickup further includes a means for transmitting a light signal to the consumption indicator when the switch is in the first position for testing electromechanical watthour meter.
The optical pickup also includes a means for detecting light adjacent the watthour meter, the detector means provided with a means for filtering ambient light and to detect the light signal transmitted from the transmitter and reflected from the consumption indicator when the switch is in the first position and further to detect a consumption light signal emanating from the electronic watthour meters when the switch is in a second position. In one aspect, the optical pickup includes a housing connected to the housing of the watthour meter test device, the housing of the optical pickup having an outer surface defining an inner retaining space.
In yet another embodiment, the transmitter and receiver are disposed substantially within the inner retaining space of the housing of the optical pickup. The housing of the optical pickup includes a first end provided with a lens to focus the light signal generatable by the transmitter to the consumption indicator of the watthour meter and further to focus the light adjacent the watthour meter to the receiver. In one aspect, the transmitter is provided with a light emitting diode for transmitting the light signal, while in other embodiments the transmitter is provided with a laser diode. The transmitter may include a fiber optic line and a collimated lens, such that the collimated lens collimates the light emitted from the light emitting diode onto the fiber optic lens.
In other aspects, the transmitter means includes a means for generating a modulated light signal at a specific frequency and the receiver means includes a means for detecting the light signal modulated at the frequency of the light signal transmitted by the transmitter means.
In yet other embodiments, the demodulation detector is active in a switch first position and wherein the modulation detector is inactive in a switch second position.
One advantage of the present invention is that the switch is provided for switching the watthour meter testing device for testing electromechanical and electronic watthour meters. The switch provides the ability for one device to test a wide-range of watthour meters.
Another advantage of one embodiment of the present invention is that when detecting light emitting from electronic watthour meters the ambient light is filtered to increase accuracy and provide maximum detection. When detecting electromechanical watthour meters, the transmitted light may be modulated at a specific frequency. The receiver may be provided with a modulation detector to detect the light transmitted within the specific frequency range.
By transmitting and detecting light at a specific frequency, detecting black marks and other indicia on electromechanical meters may be accomplished with greater accuracy and efficiency.
Another embodiment of the present invention advantageously provides an optical pickup having a wide spectrum light detector for detecting light with a wide range of spectrums. This is advantageous for detecting, among others, the wide color range of lights emitted from electronic meters.
In one aspect, the optical pickup may be provided coupled to an arm having a first portion pivotally coupled to a second portion. In this aspect, the arm may be magnetically or otherwise positionable adjacent the watthour meter to be tested. In this aspect, the optical pickup may be provided with a communication line coupleable to a processing component or other device communicating with a socket wherein a watthour meter is to be tested. Thus, the optical pickup of the present invention may be advantageously utilized by testing devices provided with unitary or modular sockets and the optical pickup may be temporarily coupled to such device for these purposes.
Other objects, features, and advantages of the present invention will be apparent to those skilled in the art from the following detailed description when read in conjunction with the accompanying drawings and appended claims.